What does "grounding at the service entrance" refer to?

Grounding at the service entrance refers specifically to the practice of establishing a connection to the ground at the main entrance point where electrical service enters a building. This is a critical safety measure because it helps to protect both the electrical system and the occupants of the building from electrical faults and surges. By grounding at this point, any excess electricity, such as from a lightning strike or surge, can safely dissipate into the earth, reducing the risk of damage to electrical equipment and minimizing the likelihood of electric shock to individuals.

This grounding method aligns with electrical codes and standards which require that all electrical services have an effective grounding system at their point of entry. It is essential to have a solid understanding of this concept for both safety and regulatory compliance. In contrast, grounding at secondary panels, grounding telephone lines, or grounding transformers serve different functions and are not the primary focus at the service entrance itself, making them less relevant in this context.